Azalea hybrid variety named `Conleb`

ABSTRACT

A new and distinct variety of azalea found as a seedling in a planned cross between the female azalea `watchet` and the male Rhododendron oldhamii `Fourth of July`. The new variety possesses a unique blooming time and is superior in development of a dense, globose shaped plant with attractive rosebud shaped flower buds and single to semi-double strong red flowers.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct variety of evergreenazalea of the genus Rhododendron and a member of the Ericaceae family.This new azalea variety, hereinafter referred to as `Conleb`, wasdiscovered by Robert Edward Lee of Transcend Nursery in August, 1986 inIndependence, La. `Conleb` originated from a planned cross hybridizationbetween two selected breeding lines in a controlled breeding program inIndependence, La. The value of this new cultivar lies in its uniqueblooming period, bloom color, bloom form, and growth habit.

Asexual propagation of the new plant by cuttings has been under Mr.Lee's direction at the same location. Several generations of the newplant have been evaluated and the distinctive characteristics of theplant have remained stable. The plant cannot be reproduced true fromseed.

SUMMARY OF THE INVENTION

The following are the most outstanding and distinguishingcharacteristics of this new cultivar when grown under normalhorticultural practices in Independence, La.

1. The unique spring, summer, and fall blooming.

2. A strong red flower color Red Group 44A with dotting color Red Group53B.

3. Single to semi-double flower with wavy petal margins. The flowersrange in size from 21/2"-23/4" in diameter.

4. Easily propagated with semi--hardwood cuttings in late spring throughthe summer.

5. Fast growth rate under normal fertilization and moisture conditions.

6. Dense and globose in nature.

7. Good specimen plant.

8. Desirable in planters.

9. Makes a very good low-growing hedge or screen.

10. Very good foundation plant.

11. Does well as an understory plant in a woodland garden.

12. Hardy to Zone 7.

13. Attracts butterflies.

DESCRIPTION OF THE DRAWINGS

This new azalea hybrid variety is illustrated by the accompanyingphotographic prints in which:

1. FIG. 1 is a close-up showing flower, foliage, and stem color as wellas flower form. The attractive rosebud-shaped flower bud is also shown.

2. FIG. 2 shows the dense and globose growth habit of a young threegallon plant.

3. FIG. 3 shows a young crop of three gallon plants in July just as theybegin to bloom.

4. FIG. 4 shows the effective use and nature of use of the new varietyin an established landscape planting.

The colors shown are as true as is reasonably possible to obtain byconventional photographic procedures. The colors of the various plantparts are defined with reference to The Royal Horticultural SocietyColor Chart. Description of colors in ordinary terms are presented whereappropriate for clarity in meaning.

BOTANICAL DESCRIPTION OF THE PLANT

The following is a detailed description of the new variety azalea basedon my observations made of plants grown in wholesale commercialproduction practices, in greenhouses, and in established landscapeplantings in Independence, La.

Distinctive Characteristics

    ______________________________________                                                                     R. oldhamii                                                                   `Fourth of                                       Characteristic                                                                          `Conleb`  `Watchet`                                                                              July`   R. oldhamii                              ______________________________________                                        Height (Mature)                                                                         4-5'      2-3'     8-10'   8-10'                                    Width (Mature)                                                                          5-6'      3-4'     6-7'    6-7'                                     Flower Size                                                                             21/2-23/4"                                                                              31/2-33/4"                                                                             13/4-21/4"                                                                            13/4-21/4"                               Flower Form                                                                             Single/   Single   Single  Single                                             semi-double                                                         Flower Color                                                                            Red G. 44A                                                                              Red      Red G. 39A                                                                            Red G. 39A                                                   G. 49B                                                    Flowers per                                                                             2-3       1-2      2-4     2-4                                      Terminal                                                                      Bloom Period                                                                            April                      Mid-May >                                                                     Mid-June                                 Bloom Period                                                                            Late July >                                                                             May      Mid-June >                                                                            Sporadic >                                         Frost              Frost   summer                                   Petal Number                                                                            5-14      5        5       5                                        Hardy Zone                                                                              7         6        7       8                                        Stamen Number                                                                           0-9       10       7-10    7-10                                     Stamen Type                                                                             Some      Non-     Non-Petaloid                                                                          Non-Petaloid                                       Petaloid  Petaloid                                                  ______________________________________                                    

The female, or seed parent, of `Conleb` is the azelea `Watchet`; amoderate pink, single, late blooming, low compact grower. `Watchet` isan unpatented Robin Hill hybrid developed by Robert Gartrell in Wycoff,N.J. Mr. Gartrell started his hybridizations in 1937 to produce hardy,late blooming azaleas. `Watchet` is the result of a cross between theSatsuki hybrid `Amagasa` and the Robin Hill Hybrid `Lady Louise`.

The male, or pollen, parent is Rhododendron oldhamii `Fourth of July`which originated from a R. oldhamii seed lot collected in 1968 by Dr.Hsu of Taiwan University. The seeds were collected at 850 meterselevation on Mount Tai Tun in Taiwan. Soon after this John Patrick ofOakland, Calif. was visiting Taiwan collecting plant material of theTaiwanese Rhododendrons. He obtained a number of seedlings from Dr. Hsuand grew them in Oakland, Calif. In 1973, Dr. John T. Thornton of C&TNursery in Franklinton, La. obtained one of the Rhododendron seedlingsfrom Mr. Patrick. Dr. Thornton noticed in the next few years that thisparticular R. oldhamii plant was a perpetual bloomer from late Juneuntil frost on new growth. This plant produces two flushes of growthcontaining flowers. The second flush of growth overlaps the first flushproducing a plant which blooms continuously. This differs from thespecies R. oldhamii which blooms from mid-May until mid-June andsporadically through the summer. Dr. Thornton subsequently named thisplant R. oldhamii `Fourth of July` in 1972.

The azalea `Fourth of July` seems to be hardy to about 10 degrees F(zone 7). Temperatures below this cause dieback, but the plant readilyrecovers and blooms profusely the following summer. R. oldhamii is lesshardy at zone 8.

Robert Edward Lee's hybridization program was conducted with emphasis onspecies that are not commonly found in the genetic make-up of thepresent day hybrids. The `Fourth of July` cultivar which Mr. Leeobtained from Dr. Thornton in 1981 is a heavy summer and fall bloomingplant, not like the Rhododendron Species Foundation form. The flowerbuds form on new growth and start blooming about July 1. Mr. Lee usedthis species to cross with existing hybrids which have a tendency tobloom in the fall and which are also fairly hardy. As expected theresulting seedlings are heavy summer and fall bloomers with veryimpressive spring blooms also.

Classification:

Botanic.--Rhododendron hybrid `Conleb`.

Form: Dense and rounded.

Texture: Medium.

Height: 4-5'.

Width: 5-6'.

Growth habit: Dense and globose. Fast growth rate under normalfertilization and moisture conditions.

Growth rate: In a period of six years from a rooted cutting the plantreaches a height of 3 feet and a spread of 4 feet. The growth rate isnormally about 8 to 10" per year; the plant reaches a height of 4 to 5'at maturity while maintaining a dense habit due to the abundant branchdevelopment.

Foliage: Alternate, simple, evergreen, pubescent, elliptic, and varyingin size from 13/4" to 21/4" long and 5/8" to 7/8" wide. The margins areentire, with a petiole 1/4" to 1/241 long. Midveins and laterals areimpressed on the upper leaf surface and prominent on the underside. Thebase of the leaf is cuneate to attenuate and the apex is acute tomucronate. The upper surface of the immature leaves are dull, pubescent,and are Yellow-Green Group 144A and the underside is Yellow-Green Group146D, pubescent, and matte. The upper surface of the mature leaves areYellow-Green Group 146A, dull and slightly pubescent and the undersideis Yellow-Green Group 146C, matte, and pubescent. New growth ispubescent. These hairs are initially soft and white and cover both sidesof the leaf with a higher concentration on the petioles and veins. Theyare slightly curled, flat, and range in length from 1/32" to 1/16". Asthe growth matures much of the leaf pubescence is lost; however, thestems, petioles, and leaf veins retain this pubescence which becomesmore setaceous and darker in color (Brown Group 200A) through thegrowing season.

In 1994, the date of initial spring growth was March 10, inIndependence, La. After the initial spring flush there was almostcontinuous growth until that fall ending Oct. 23, also in Independence,La. When grown in full sun, the internode length of this plant is 5/16"to 11/16"; when grown in light shade the internode length is 3/8" to3/4". As would be expected a plant grown in shade results in a taller,less dense plant with larger leaves.

The average length of terminal growth of the initial spring flush isabout 5" for a plant in full sun and about 7" when grown in shade. Thisgrowth should not be trimmed since it will produce flowers starting inlate July. As the plant continues to grow through the summer and fallmore flower buds are produced, which mature and bloom until frost. Thisremaining growth produces about 4" to 5" of height. As cool weatherapproaches, some of the flower buds become dormant. These buds bloom inApril of the next year.

Stems: The young stems are Yellow-Green Group 146C and densely clothedwith spreading white glandular hairs. During the second growing seasonthey become Greyed-Green Group 197B, glabrous and rugose. The immaturepetioles, midribs, and veins are also Yellow-Green Group 146C. The pithis solid and uniform. Young and older stems are densely branched.

Buds: Tight buds at 1/2" are ovate and acuminate Yellow-Green Group 146Dwith a hairy pubescence Brown Group 200A. The buds are borne in clustersof 2 to 3, and are sheathed by a pair of modified leaf bracts which arefrom 1/4" to 1/2" long, persistent, and Yellow-Green Group 147A. Thepedicel is 3/8" to 1/2" long, pubescent, and Red Group 53B. The calyx is1/4" to 3/8" long, Yellow-Green Group 144A, funnel shaped, persistent,and pubescent. The five imbricated sepals are lanceolate and joined atthe base to form a cup. As the buds swell the bud sheath matures to aGreyed-Orange Group 165A, falls off, and reveals the flower color RedGroup 42A. The petals have a rose bud shape as they begin to open.

Flowers: Perfect, single to semi-double, Red Group 44A (front and back),glabrous, openly funnel shaped, 21/2" to 23/4" wide by 21/4" to 21/2"long, borne on current season's growth, non-fragrant; they last on theplant in the garden 5 to 6 days. There are 5 true petals which are fusedat the base, elliptic to obovate, and have wavy margins. The dorsal lobeand the two upper wings of these true petals are dotted Red Group 53B.There are from 0 to 9 short stamen which are often petaloid. Thepetaloid stamen are from 1/2" to 11/2" long and are odd shaped. Thenon-petaloid stamen are 1/4" to 1/2" long and the filaments are RedGroup 44A. The anthers are Red Group 44A and the pollen is Yellow Group11 B. The pistil is single, non-petaloid, 13/4" to 2" long, and RedGroup 46A. The ovary is densely glandular-setose and has five locules.The capsule matures in about 5 months, in Independence, La. to about1/4" to 1/2" long; it has a persistent style, is Yellow-Green Group146A, and contains from 100 to 300 nonwinged seeds. Normally fruit setis not heavy. There is a 2 to 3 week flowering period in April inIndependence, La. Flowering resumes in late July as the new buds matureand continues until frost which can be as late as November or Decemberin Independence, La. Azaleas blooming at this time of year attractbutterflies in profusion.

Culture: Grows well in a wide range of conditions, tolerates sun toshade. Prefers a moist, well-drained soil that is rich in organicmatter. Responds well to mulching and medium applications of fertilizer;prefers ph 5.0 to 5.5. Very little pruning is needed; adaptable tocontainer and above ground planters; makes a good foundation plant orinformal hedge with excellent foliage and flower contrast. Ideal forcoastal regions and warmer parts of Piedmont. Propagated withsemi-hardwood cuttings in late spring through the summer.

Pests: Lace wing and spider mites can be a problem.

I claim:
 1. A new and unique variety Azalea hybrid plant named `Conleb`as herein shown and described.